Periop Med Flashcards
PERIOP MED (Psych/drugs) - Methamphetamines
[20B11] Discuss the perioperative implications for a patient known to use methamphetamine.
!! [24B01]
Outline the perioperative management of a methamphetamine
intoxicated 20‑year old who requires urgent surgery.
Drug effect on behavour =
Mimic - endogenous monoamines (sympathomimetic) –> excitation and euphoria
- CVS
- Sympathomimetic - Resp
- smoking +/- PHTN - Metabolic
- Hyperthermia
- Met acidosis
- rhabdo
- malnutition
Acute vs chronic use
Chronic
- withdrawal, dependence, comorbidities
Hx
- drug / duration
- comorbidities
Ex
- intox –> consent?
Ix
- viral
- ECG - long QT
consent?
aggression –> BZD?
** INTRAOP = BP and vol**
1. BP - labile -
2. Aim euvolaemia
Postop = WD and refer*
- monitor withdrawal - sleep/eat/depress
- psych / A&D
24B01
Minimum Criteria:
* Considers drug effects on behaviour
* Considers consent responsibilities
* Considers reasons for urgent surgery (i.e. going ahead whilst intoxicated)
* Mentions physiological effects of methamphetamine toxicity with some reference to how this influences intraoperative management
* Postoperative problems are anticipated
Poorly scoring answers frequently omitted discussing the consent process and postoperative
issues in these patients
BT_PO 1.5
MAKE UP
[-] Discuss the perioperative implications for a patient known to use CANNABIS (instead of methamphetamine.)
SAD - substance abused disorder
CNS-depressant
- EtOH
- BZD
- opioids
CNS-stim
- cocaine
- amphetamines
- ecstasy
- CBD
Aim
1. Prevent w/d effective analgesia
2. Sx Rx of affective/behavioural problems
Key
1. Acute (consent) vs chronic use (poor nutrition, comorbid)
2. Difficult IV access
3. PPE
4. Post op analgesia plan
Natural vs synthetic
Oral vs pulm
Low bioavail
Long t1/2
Low tox
CBD
PM10 2019: Medicinal cannabis for chronic pain
OHA p.337
PERIOP MED (Neuro) – Parkinson’s disease
[21A06] You will be anaesthetising a 63-year-old man with severe Parkinson’s disease who is booked for an inguinal hernia repair. Discuss the issues that are relevant to providing perioperative care for this patient. (also 15A10, 09A05)
RTB
rigidity/tremor/bradykinesia
AUTONOMIC/cog/emo
Pathophys
ACh (exc) and DA (inh) imbal in BG –> loss of DA–> unopp EXC –> tremor/rigid
Drugs
- Levodopa
- Carbidopa
- DA agonist
- MAO-Bi
- COMTi
- Anti-ACH
- NMDA antag
Features
1. Cog change
2. Autonomic instability
3. Aspiration risk
4. Meds
- continue Da drugs
- avoid anti-Da )
Post op - return to meds
PERIOP MED (Neuro) – Myasthenia gravis
[20B09] A patient with myasthenia gravis presents for emergency laparotomy for small bowel obstruction.
Discuss your perioperative management of this patient including your choice of anaesthesia. (also 14B09, 06A05, 03B03)
MG
IgG autoab + POST-syn nAChR at NMJ
ocular
bulbar - aspiration
prox limb
ATIA
Dr Podcast
(60.6%) Application of knowledge of the condition and its perioperative management in the emergency setting was required here and the majority of candidates achieved a satisfactory standard.
Airway management, recognition of the emergency, assessment of severity, stability and current treatment required discussion.
Specifics relating to the implications of choice of muscle relaxants and sedative medication with post- operative considerations required discussion as did the management of the patient’s anticholinesterase therapy.
Areas where some candidates fell short included inadequately classifying the condition including the significance of bulbar symptoms, the requirement for replacement anticholinesterase therapy in the perioperative period and omitting detail of an analgesic plan in this patient (major open abdominal surgery with likely poor respiratory mechanics).
PERIOP MED (Neuro) – Peri-operative stroke
[19B13] List the risk factors for perioperative stroke. (50%)
Discuss the measures you use to ̄ perioperative stroke in high-risk patients undergoing major orthopaedic surgery. (50%) (also 12A13)
RF
patient:
1. Age > 70yo
2. F
3. Comorbin
Intraop
1. Type (cardiac/CEA)
2. Urgency (emerg > elec)
3. GA>RA>LA
4. Duration
Post op
1. AMI/AF
2. Dehyd
3. Hypergly
Periop Mx to dec stroke
1. Pre op
-
PERIOP MED (Neuro) – Traumatic SC transection at C6 (acute)
[15A14] A 40-year-old requires a laparotomy ten days after an isolated traumatic spinal cord transection at C6.
1. Outline the key anaesthetic issues. (50%)
2. How would these influence your anaesthetic management? (50%)
Key
1. Unstable C-spine
2. Neurogenic shock
3. Acute laparotomy
Neurogenic
- loss ANS
- dec BP, dec HR, peri VD
PERIOP MED (Neuro) – Longstanding C5-6 quadriplegia
[13B15] A 25-year-old female with longstanding C5-6 quadriplegia requires ureteric stent insertion. Outline the implications for anaesthesia.
PERIOP MED (Neuro) - Epilepsy
[13A05] What are the perioperative concerns for the anaesthetist managing a patient with epilepsy?
Epilepsy - common 1%
Anti-epileptic
Anaes agent ~ seizures
- IV - avoid etom/ket
- VA - avoind enf
- Opioid - avoid peth/tram
- NMBA - avoid sux(K up)/laudanosine from atrac
- LA - re ceiling dose
CYP450
Carb/pheny - indu
Valp - inhibit
PERIOP MED (GI) – Liver
[10B03] A 45-year-old man with a longstanding history of alcoholism is booked for upper gastrointestinal endoscopy and banding of oesophageal varices following an episode of haematemesis.
(a) How is the severity of this patient’s liver disease assessed? (50%)
(b) How do these findings influence your evaluation of this patient’s perioperative risk? (50%)
Liver scoring
1. MELD
- BIC - bili/INR/Cr
2. CP
- A/B/P/E/C
Extra-hepatic sequelae
1. HRS
2. HPS
Type/urgency of procedure
Type of anaes require
Comorbid
PERIOP MED (Haem) – von Willebrand disease
[19A13] Outline your approach to the perioperative management of a patient who gives a strong family history of von Willebrand disease.
Types of vWD (ISTH)
Quant def: 1 and 3
Qual def: 2
Mx Responder vs non-responder
Rx - DDAVP (desmo)
*rel vWF
Mx options
Mx - diff types of vWD
Features
1. 2050 a.a. plasma glyco
2. 1% AD chr 12mut
3. mucosal bleed
Rx:
1+2a - DDAVP
2b+3 - vWF replacement
Cryo - IIIF(fibronectin, fibrinogen, vWF), FVIII, FXIII
*F8/vWF = Humate P
PERIOP MED (Haem) – Anaemia 1
[19A10] These are the blood results of a 65-year-old man scheduled for a revision total hip replacement.
- Interpret these results (30%)
- How would you manage this patient preoperatively? (70%)
DDx
Micro/Normo/Macro
1. Hb
2. MCV - M/N/M
- IDA
- Ferritin <30
- Non-IDA
- Ferritin > 100
Optimise
PERIOP MED (Haem) – Minimising blood loss and transfusion
[15B03] An adult patient is scheduled for a major operation during which significant blood loss is expected. Describe strategies you would consider perioperatively when planning to minimise blood loss and transfusion requirement.
Key strategies PBM
*1. Mx anaemia
*2. Min BL
*3. Imp tol to anaemia
PERIOP MED (Haem) - VTE
[15A12] In PAC, you are assessing a patient who is concerned about the risk of developing venous thromboembolism (VTE) perioperatively.
a) Outline the patient factors that increase the risk of VTE. (50%)
b) Describe measures that may reduce the risk of perioperative VTE (50%)
(83.4%) Candidates were expected to at least mention
- a) Previous history/family, obesity, cancer and oestrogen containing pills
- b) Measures would include minimising the preop, intraop and postoperative risks
Background
(also 08B05, 05A02)
RF = virchows triad
Stasis, hypercoag, endo dam
Mx
1. Preop
a. STRATIFY
- Intraop
a. GCS
b. IPC
c. Pharm - Postop
a. Mob early
PERIOP MED – Addison’s disease
[21B08] Discuss how a diagnosis of Addison’s disease would influence your perioperative management of a patient who requires an urgent laparotomy for bowel obstruction.
Addison dx
- hypoTension
- low cortisol (GC) and aldosterone (MC)
Effect (add crisis from stress)
1. BGL low
2. Na low
3. K High
4. Urea high
Mx
1. Fludrocort
2. Hydrocort (GC+MC)
Preop
- C - consult endocrine
Intraop
1. IAL for BP monitoring
2. Electrolytes - Na/K
3. Steroid cover
- Hydrocortisone
- Dex 6-8mg - good for 24h
x dex - no MC activity
Post op
1.
PERIOP MED (Endocrine) – T2DM
[19A03] a) List the causes of increased perioperative morbidity and mortality in surgical patients with type 2 diabetes mellitus. (30%)
b) Outline the principles of perioperative management of these patients. (70%)..
(also 17A05, 09B02, 06A03)
Key
1. HbA1c <8.5% (postop if > 9)
2. BSL perio op: 5-10mmol/L
Perio
Meds
1. OHA - WH DOS
2. SGLT-2 - WH 2/7 prior + DOS
- If Ket > 1 and pH < 7.3/ HCO3 < 15 –> ivf + ins/dex
Patients with type 2 diabetes mellitus (T2DM) face elevated perioperative risks due to metabolic and vascular complications. Effective management requires preoperative optimisation, vigilant glucose monitoring, and tailored medication strategies to mitigate these risks.
a) Causes of increased perioperative morbidity and mortality
1. Hyperglycaemia-related complications:
- Increased postoperative infections (surgical site, respiratory, urinary)[1][7]
- Acute kidney injury and metabolic acidosis[7][8]
- Delayed wound healing and higher reoperation rates[7][8]
-
Macrovascular disease:
- Myocardial infarction and cardiovascular instability[2][8]
- Peripheral vascular disease exacerbating ischemia[7]
-
Microvascular complications:
- Neuropathy increasing aspiration/pressure injury risks[2]
- Retinopathy and nephropathy complicating fluid management[4][8]
-
Metabolic instability:
- Hypoglycaemia from fasting/medication mismanagement[6]
- Diabetic ketoacidosis/hyperosmolar states in severe hyperglycaemia[2]
-
Stress response:
- Surgery-induced insulin resistance and hepatic glucose overproduction[2][9]
b) Perioperative management principles
1. Preoperative optimisation
- Glycaemic control:
- Target HbA1c 8.5% (69 mmol/mol)[3][6]
- Avoid fasting >6 hours for solids/2 hours for clear fluids[4][6]
-
Medication adjustments:
- Stop 48h pre-op: SGLT2 inhibitors (risk of euglycaemic DKA)[9]
- Stop 24h pre-op: Metformin (renal safety), GLP-1 agonists (delayed gastric emptying)[5][6]
- Continue: Basal insulin with dose reduction (e.g., 80% of usual if fasting)[5][6]
2. Intraoperative management
- Blood glucose targets: 5–10 mmol/L (90–180 mg/dL)[5][6]
- Monitoring: Hourly BSL checks using point-of-care testing[5][9]
- Insulin strategies:
- Minor surgery: Subcutaneous rapid-acting insulin corrections[5]
- Major surgery: IV insulin infusion (e.g., 0.5–2 U/hr) with 5% dextrose[5][6]
3. Postoperative care
- Monitoring: 1–2 hourly BSL until stable, then 4-hourly[5][6]
- Reinstate medications when eating normally:
- Restart metformin 48h post-contrast/after renal function confirmed[5]
- Transition IV insulin to subcutaneous regimen using 80% of pre-op basal + mealtime corrections[9]
- Complication prevention:
- Early mobilisation to reduce thrombosis risk[4]
- Aggressive infection surveillance[6][8]
4. Special considerations
- Emergency surgery: Prioritise fluid resuscitation + IV insulin to correct hyperglycaemia/ketosis[9]
- Day surgery: Schedule as first case; use glucose-potassium-insulin infusions if prolonged fasting[4][6]
Australian guidelines emphasise individualised care, with protocols from the Australian Diabetes Society (ADS) and ANZCA recommending multidisciplinary coordination to address both surgical outcomes and long-term diabetes control[6][9]. Key gaps in suboptimal responses include omitting specific BSL targets, inadequate medication transition plans, and underestimating fasting duration impacts.
Citations:
[1] https://www.diabetessociety.com.au/documents/PerioperativeDiabetesManagementGuidelinesFINALCleanJuly2012.pdf
[2] https://pmc.ncbi.nlm.nih.gov/articles/PMC8394235/
[3] https://pmc.ncbi.nlm.nih.gov/articles/PMC6455978/
[4] https://www.cpoc.org.uk/sites/cpoc/files/documents/2021-03/CPOC-Guideline%20for%20Perioperative%20Care%20for%20People%20with%20Diabetes%20Mellitus%20Undergoing%20Elective%20and%20Emergency%20Surgery.pdf
[5] https://pmc.ncbi.nlm.nih.gov/articles/PMC5692120/
[6] https://perioptalk.org/wp-content/uploads/2013/11/diabetes-guidelines-website.pdf
[7] https://pubmed.ncbi.nlm.nih.gov/23834046/
[8] https://pmc.ncbi.nlm.nih.gov/articles/PMC9204286/
[9] https://www.diabetessociety.com.au/guideline/ads-anzca-perioperative-diabetes-and-hyperglycaemia-guidelines-adults-november-2022/
[10] https://www.tandfonline.com/doi/full/10.1080/17446651.2023.2272865
[11] https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2022.841256/full
[12] https://emedicine.medscape.com/article/284451-overview
[13] https://thewomens.r.worldssl.net/images/uploads/fact-sheets/Diabetes-surgery-0518.pdf
[14] https://www.wjgnet.com/1948-9358/full/v12/i8/1255.htm
[15] https://medlineplus.gov/ency/patientinstructions/000702.htm
[16] https://diabetesjournals.org/spectrum/article/15/1/44/890/Management-of-Diabetes-Mellitus-in-Surgical
[17] https://jamanetwork.com/journals/jamasurgery/fullarticle/2793063
[18] https://academic.oup.com/bjaed/article/17/4/129/2629524
[19] https://asmbs.org/patients/surgery-for-diabetes/
[20] https://www.cpoc.org.uk/guidelines-and-resources/guidelines/guideline-diabetes
[21] https://www.diabetessociety.com.au/ads-anzca-perioperative-hyperglycaemia-guidelines-adults/
[22] https://www.ncbi.nlm.nih.gov/books/NBK540965/
[23] https://www.diabetessociety.com.au/wp-content/uploads/2023/03/ADS-ANZCA-Perioperative-Diabetes-and-Hyperglycaemia-Guidelines-Adults-November-2022-v2-Final.pdf
[24] https://pharmaceutical-journal.com/article/ld/perioperative-management-of-type-2-diabetes-mellitus
[25] https://www.diabetessociety.com.au/guideline/ads-peri-operative-diabetes-management-guidelines/
[26] https://libguides.anzca.edu.au/pomtrain/U3M10
[27] https://www.diabetesaustralia.com.au/health-professional-guidelines/
[28] https://anaesthetists.org/Home/Resources-publications/Guidelines/Peri-operative-management-of-the-surgical-patient-with-diabetes
[29] https://asa.org.au/wp-content/uploads/2024/10/ASA-FS1-Perioperative-Management-of-Patients-on-GLP-1-Receptor-Agonists-GLP-1-RAs.pdf
[30] https://pmc.ncbi.nlm.nih.gov/articles/PMC9131255/
[31] https://webstor.srmist.edu.in/web_assets/srm_mainsite/files/files/Surgical%20complications%20of%20Diabetes.pdf
[32] https://catag.org.au/wp-content/uploads/CATAG-Topic_Diabetes_Practice-Tool_F.pdf
[33] https://pmc.ncbi.nlm.nih.gov/articles/PMC10375498/
Answer from Perplexity: pplx.ai/share
PERIOP MED (Endocrine) – T2DM + autonomic neuropathy
[16B14] A 45-year-old male with long standing diabetes is scheduled to undergo elective laparoscopic cholecystectomy.
a) In the preanaesthesia assessment clinic, how would you assess this patient for the presence of diabetic autonomic neuropathy? (50%) b) Discuss the anaesthetic implications of his autonomic neuropathy. (50%) (also 11A15, 05B03)
AN
- DM, PD etc
Ax (AUTONOMIC NEUROPATHY)
CVS
* Hydrostatic hypotesnvie
GI
- Gastroparesis -
GU
- impotence
- retention
Thermoreg
- loss of sweating
b) Implications
*Impaired BRR + inability to inc HR –> fixed CO
Intraop
- IDC
- preload
- pre-emp vasopressor
- resp++ to laryngoscopy
- asp risk
Post op
- silent ischaemia
PERIOP MED (Endocrine) – T2DM + HTN
[13B01] A 68-year-old man is scheduled for total knee replacement next week.
He has hypertension, for which he is prescribed enalapril, and type 2 diabetes, for which he is prescribed metformin.
Justify your perioperative management of his medications.
- Periop Risk strat
- Maintain “normal”
- GL+RECOMM!!
- Risk/Ben calc
General
1. Withdrawal
2. Disease progress
3. Interaction with anaes
4.
Controlled?
Omit both DOS
Consider
1. Anxiolytic - avoid stress
2. Intraop HTN - clon/hydral
3. Intraop BGL - freq measure + insulin inf
4. Resume meds ASAP post op
PERIOP MED (Endocrine) - Carcinoid syndrome
[18B11] Discuss your perioperative management of a patient with carcinoid syndrome presenting for small bowel resection.
sx by NE tumour secreting VASOACTIVE subs
- triad - heart/diahhoea/flushing
PREMED Rx - octreotide
50mcg/hr IV 12hr preop
Intraop
- Prop/Remi
Conflicts:
- RSI vs titr ind
- RSI vs avoid sux
- deep anes vs CV dysfx
POSTOP:
ICU/HDU - vol/elec/bsl/HD
wean octreotide
PERIOP MED (Endocrine) - Thyroidectomy
[17B08] Discuss the preoperative assessment for a patient who presents for thyroidectomy.
Mass effect, potential AW problems, adj structures, endocrine issues
Mass effect
1. AW
2. SVC return
PERIOP MED (Endocrine) - Acromegaly
[14A13] A 53 year-old man with acromegaly presents for a transphenoidal resection of his pituitary tumour.
a) Outline the features of acromegaly. (50%)
b) How does this diagnosis influence your anaesthetic management? (50%) (also 08A12)
Acro features
Heart + AW
DM/HTN/LVH/OSA
DHLO 30405060%
Dx:
1. Inc IGF-1
2. GH supp test
Rx:
1. Sx - pit macroadenoma
2. Adj. SOMATOSTATIN analogue
3. GH-r ANTAG (pegvisomat) (nonresp)
4. Pit irradiation
Pre:
1. AW ax
2. visual ax
3. OSA
4. CVS
Intraop
1. Secure DA
2. Crisis
a) post op stridor
b) endo emerg: DI, SIADH
3. Difficult access + IAL
- positioning
- HTN
- VAE
Postop
1. HDU/ICU
2. Upper CN signs
3. Hormonal supp - ?hydrocort
4. CSF leak, DI
PERIOP MED (Autoimmune, congenital, acquired) – Rheumatoid arthritis
[20A15] Discuss the anaesthetic considerations for an adult patient with rheumatoid arthritis presenting for wrist surgery. (also 02A10)
Key
1. RA severity
2. CVS/Resp involv
3. Meds
4. AA instab/AW consideration
5. Regional
6. Positioning
7. Analgesia
*DO NOT overcall
RA
- auto-infla
- symmetrical polyarthritis
- extra art involv
CR involvement
Current meds - DMARDS
steroids - >10mg = cover
MTX - ILD, hep fail
SSZ - neutro/thrombopaenia, IPF
AZA - hepatitis, BM supr
XR - ANT arch of atlas TO odontoid process > 3mm = AAS ***
Ix
1. TTE if sig SOB at rest
2. ABG if SpO2 < 95% RA or O2 Rx
3. Resp Ex + –> PFT + CXR
Intraop
1. RA > GA
2. Prep for DA, min C spine manip
3. Positioning
Post op
1. suitable for day surg
2. HDU/ICU if concerns
3. restart reg meds ASAP
4. multi modal
5. OT - hand fx important
PERIOP MED (Autoimmune, congenital, acquired) – Marfan Syndrome
[19B03] Discuss how Marfan syndrome influences your anaesthetic management for a patient requiring an urgent laparoscopic appendicectomy.
Key
1. CVS ~ BP control - laryngoscopy, pneumo and ext
2. AW issues
3. Lung path - avoid PTX 2o bullae
Marfan
- AD CT metab
- fibrillin 1 gene on chr 15
- ## stiff aortic walls
DASI and METS
VO2 peak (mL/kg) = 0.43 × DASI + 9.6
DASI 34 –> 24
METs (metabolic equivalents) = VO2 peak / 3.5
PERIOP MED (Autoimmune, congenital, acquired) - Frailty
[19A11] Define frailty and discuss the role of prehabilitation for patients with frailty.
Frailty
- multidimensional
- depletion of physiological reserve
- vulnerable to stress
- harder to recover from illness
- independent RF for higher M&M
- “CLINICAL FRAILTY SCALE”
Prehab
- enhancing fx cap
- withstand stressor
- improve baseline + shorten recovery
4 approach
1. Med optimise
2. Phys exercise
3. Nutritional support
4. Psych support
Benefits (theoretical)
- improbve CR fx
- dec LOS, post op pain, post op comp
Limitations
1. limited evidence
2. variation/no std protoc
3. Cost
4. Var compliance
Prehabilitation
https://academic.oup.com/bjaed/article/17/12/401/4083340
PERIOP MED (Autoimmune, congenital, acquired) - Scleroderma
[17B09]
A 50-year-old woman with systemic sclerosis (scleroderma) presents for laparoscopic appendicectomy.
She is currently treated with folate supplements and weekly methotrexate.
Describe how your anaesthetic plan is modified by the presence of scleroderma in this patient.
Key
1. Avoid aspiration
2. potential DA (limited MO)
3. Safe vent strategy
4. Difficult monitoring
PERIOP MED (Autoimmune, congenital, acquired) – Cystic fibrosis
[17A02] A 24-year-old female with cystic fibrosis is scheduled to undergo elective breast surgery.
How does the presence of cystic fibrosis affect your perioperative management of this patient for this procedure?
PERIOP MED (Autoimmune, congenital, acquired) – Myotonic dystrophy
[16A02] A 30-year-old patient with myotonic dystrophy is scheduled for surgery for acute appendicitis.
a) Outline the important factors in the preoperative assessment of this patient. (50%)
b) Describe how this patient’s myotonic dystrophy will affect your anaesthetic management. (50%)
RESP ISSUES
*RLD + OSA
Myotonia = prolonged muscle contraction
Dystrophy = muscle wasting
Dystonia = atrophy + contraction
DM (1 - chr 19; 2 - chr 3) and MC
Muscle dystrophy = progressive weakness
INHERITENCE
Main = x linked = DMD and Becker
CF
Systems
1. AW/Resp = bulbar, RLD
2. CVS = CM , MCP
3. GI = delayed motility –> ASPIR
Anaes
1. Sux - X - K+ myo contracture
2. Sens to CNS depress
3. Neo - X - Myo cont
PERIOP MED (Psych/drugs) – Cease smoking
[16A11] As a perioperative physician, what strategies can you offer to assist a patient to cease smoking tobacco and how will you best communicate them? (also 09B14)
2 parts to the Q
(79%) Borderline standard: To achieve a pass candidates needed to describe a reasonable non- pharmacological intervention that is effective in the medium to long term AND have a grasp of at least one suitable replacement therapy.
- Non-pharm intervention Med/long term
a. Indiv counselling
b. GBT
c. rapid smoking aversive therapy - Replacement therapy
NRT - patch/gum/strips - Pharm
NrPA - varenicline
Bupropion
Nortriptyline
Clonidine
Communicate
AAR - ask/advice/refer
Benefits
PG12(POM) Perioperative smoking 2014
Smoking Cessation Benefits
Whic PG?
1 day = low COHb
3 weeks = improve skin healing
6mo = imm fx
PG12(POM) Perioperative smoking 2014
PERIOP MED (Psych/drugs) – Chronic alcohol misuse.
[15B12] A 47 year old man presents to the emergency department with acute abdominal pain requiring a laparotomy.
He is known to have chronic high intake of alcohol.
Describe how chronic alcohol misuse will affect your perioperative management of this patient.
BG
Pre
Hx
Intra
RSI likely
Inc anaes req
HD instab likely
Post
Post op del
post op w/d
Analgesia
PERIOP MED (Other) – POSSUM Score, SORT score
[20A04] The Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM) and the Surgical Outcome Risk Tool (SORT) are examples of risk scoring systems used for predicting postoperative morbidity and mortality.
Evaluate the strengths and weaknesses of these types of risk scoring systems in clinical practice.
POSSUM
- 2 part
- 12 phys var
- 6 op var
- 16-136
- 30 day M&M rate
SORT (2011)
- UK, non cardiac/NROS/obs/txp
- 30 day M&M
- 6 perop var
Strength of SCORING SYS in gen:
1. Better than clinical judgement alone
2. Allows shared decision making with patient and surgeon
3. Improved preoperative planning
CONS
1. Not predictive for the individual patient
2. May not apply to your specific hospital or population
3. SUBJECTIVE data points
Additional (Bluebook 2023)
Ideal
1. High acc
2. Good disc
3. Good cali
4. Local validated
- Wide applicability
- Versatile
- Simple to use
- Parsimonius
- Transparent/explainable
- Regularly pdated
- Compliance
Perioperative steroid / glucocorticoid management
Therapeutic GC
1. Hydrocort ~ cortisone
2. prednisolone
3. DEX
- Hydrocortisone 100mg then 200mg/24hrs
- Dex 6-8mg (good for 24 hrs)
Guidelines for the management of glucocorticoids during
the peri-operative period for patients with adrenal
insufficiency
Guidelines from the Association of Anaesthetists, the Royal College of Physicians and the Society for Endocrinology UK
Anaesthesia 2020
PERIOP - MINS
MINS Mx Postop
Periop Risk Calc
Evaluate
[MADEUP] Discuss the perioperative implications for a patient known to use cannabis.
This was a poorly answered question with many answers demonstrating a lack of appreciation of the multiorgan effects of cannabis / cannabinoid products use by patients that are relevant to anaesthesia.
An answer was required to discuss:
The various oegan system effects and the issues that impact on
management throughout the perioperative period.
Cannabis use has significant perioperative implications affecting multiple organ systems, requiring tailored management strategies. Below is a systematic analysis of key considerations:
Central Nervous System Effects
1. Altered Pain Perception
- Cannabis users demonstrate 30% higher postoperative opioid consumption (adjusted ratio of geometric means 1.30) and elevated pain scores (mean difference 0.57/10) compared to non-users[1][3].
- Proposed mechanisms:
- CB1 receptor downregulation causing opioid cross-tolerance[2].
- Disruption of endogenous cannabinoid-opioid synergy[2].
2. Anesthetic Interactions
- Increased propofol requirements reported in human studies (e.g., 23% higher induction doses)[2].
- Potential for prolonged emergence due to THC’s lipophilic accumulation in adipose tissue[2].
Cardiovascular Effects
- Tachycardia (via CB1 agonism) and hypotension (reduced systemic vascular resistance) are common[2].
- Risk of myocardial oxygen supply-demand mismatch in patients with coronary artery disease[2].
Respiratory Complications
- Bronchial hyperreactivity: Chronic inhalation causes tracheobronchial mucosal inflammation, increasing risks of:
- Perioperative bronchospasm[2].
- Atelectasis (2.0% vs 2.4% in non-users)[3].
- Vaping-associated lung injury: FDA warns of severe pulmonary disease linked to THC oil vaping[2].
Gastrointestinal & Hepatic Considerations
- Cannabis Hyperemesis Syndrome: Cyclic vomiting may complicate fasting/NPO status[2].
- CYP450 Interactions:
- THC/CBD inhibit CYP3A4/2D6, altering metabolism of opioids (e.g., oxycodone) and benzodiazepines[2].
- Requires dose adjustments for drugs like clobazam[2].
Immune Modulation
- Preclinical data suggest immunosuppression at high doses (impaired cell-mediated immunity), though clinical relevance remains unclear[2].
Pain Management Strategies
1. Multimodal Analgesia: Prioritize NSAIDs, acetaminophen, and regional techniques to offset increased opioid needs[1][3].
2. Opioid-Sparing Protocols: Anticipate 30% higher 24-hour morphine equivalents in cannabis users[1].
3. Avoid Opioid-Benzodiazepine Combinations: Synergistic sedation increases risk of ventilatory impairment[2].
Preoperative Optimization
- Screening: Explicitly document use patterns (frequency, route, last exposure). Urine THC testing if history unclear[1].
- Cessation Counseling: Ideal abstinence duration unknown, but ≥72 hours pre-op may reduce airway reactivity[2].
Intraoperative Considerations
- Airway Management: Higher risk of laryngospasm/bronchospasm; consider IV lidocaine pre-intubation[2].
- Hemodynamic Monitoring: Anticipate THC-induced tachycardia; avoid epinephrine-containing local anesthetics[2].
Postoperative Vigilance
- Respiratory Monitoring: Despite no significant hypoxia association in large studies[1], monitor for apnea in opioid-naïve users.
- Withdrawal Symptoms: Agitation, insomnia, or hyperalgesia may manifest 24-72 hours post-op in heavy users[2].
Key Knowledge Gaps
- Long-term outcomes of perioperative cannabis use remain understudied.
- Optimal management of synthetic cannabinoids (e.g., Spice, K2) lacking evidence[2].
Conclusion
Perioperative teams must adopt a proactive approach: anticipate increased analgesic requirements, optimize pulmonary function, and mitigate drug interactions. Multidisciplinary planning is essential for safe outcomes in cannabis-using surgical patients.
References[1] Ekrami et al. Anesth Analg. 2024;139:724-733.[2] Tapley & Kellett. Cannabis-based medicines and the perioperative physician. 2019.[3] Nathan. Cannabis on the Rise: Are Perioperative Risks as Well? 2024.
Citations:
[1] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/8660e6e7-9e0c-43b2-a990-d75614fb8038/cannabis_on_the_rise__are_perioperative_risks_as.7.pdf
[2] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/1ece06eb-3290-4d80-9c31-8ffde436431c/Cannabis-based-medicines-and-the-perioperative-physician.pdf
[3] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/29bab42d-7f63-46b4-bfca-c979305a8adf/association_between_cannabis_use_and_opioid.8-2.pdf
[4] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/8660e6e7-9e0c-43b2-a990-d75614fb8038/cannabis_on_the_rise__are_perioperative_risks_as.7.pdf
[5] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/1ece06eb-3290-4d80-9c31-8ffde436431c/Cannabis-based-medicines-and-the-perioperative-physician.pdf
Answer from Perplexity: pplx.ai/share
Mnemonic: CANNABIS
Use the drug’s name to remember key perioperative implications:
-
Cardiovascular effects
Tachycardia, hypotension, myocardial oxygen mismatch. -
Analgesia requirements
30% higher opioid consumption, use multimodal strategies. -
Neurological considerations
Altered pain perception, prolonged emergence from anesthesia. -
Nausea management
Cannabis Hyperemesis Syndrome may disrupt fasting. -
Airway reactivity
Bronchospasm risk; consider IV lidocaine pre-intubation. -
Benzodiazepine caution
Avoid synergistic sedation with opioids. -
Immune modulation
Potential immunosuppression at high doses. -
Screening & cessation
Document use patterns, advise ≥72h pre-op abstinence.
Key Benefits
- Directly links the drug name to clinical considerations.
- Covers organ systems, pharmacology, and perioperative phases.
- Actionable for pre-, intra-, and postoperative planning.
Citations:
[1] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/8660e6e7-9e0c-43b2-a990-d75614fb8038/cannabis_on_the_rise__are_perioperative_risks_as.7.pdf
[2] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/1ece06eb-3290-4d80-9c31-8ffde436431c/Cannabis-based-medicines-and-the-perioperative-physician.pdf
[3] https://ppl-ai-file-upload.s3.amazonaws.com/web/direct-files/49558506/29bab42d-7f63-46b4-bfca-c979305a8adf/association_between_cannabis_use_and_opioid.8-2.pdf
Answer from Perplexity: pplx.ai/share
